Positive OPK the same day as ovulation

My chart shows that I ovulated the same day as my positive OPK. I thought ovulation happened the day after a positive OPK. Is it possible to ovulate the same day as getting a positive OPK?

When you are using ovulation prediction kits (or devices that measure luteinizing
hormone), you can usually expect ovulation to occur the day after your
first positive result. This is because (LH) luteinizing hormone, the hormone
measured by OPKs and the hormone responsible for triggering the rupture of the
ovarian sac, typically surges the day before ovulation. In some cases, however,
you will see ovulation on the same day as the positive result. There are a few
factors that can help explain how this happens.

First, remember that when you are reading your OPK, you are seeing a snapshot
of your LH surge. You do not really know whether you are seeing the beginning,
peak or trail of the surge. What you know is that your LH is at a level that
is detectable as a surge by the kit. It may have started to surge soon after
your test the previous day and be starting to trail, or it may be just starting
to surge. In a case where it looks on the chart as if ovulation occurred the
same day as the surge, here is what may have happened:

1. LH started to surge during the night or early in the morning and was detected
by your OPK in the early afternoon.

2. Ovulation occurred sometime in the evening or night, several hours after
your positive OPK, possibly several hours longer than when the LH actually started
to surge.

3. Your temperature is up in the morning, indicating ovulation for the previous
day, the same day as the positive OPK, even though many hours have elapsed between
the LH surge and your temperature rise.